Currently monitoring of skier/skiing performance relies on few techniques, such as: skier feelings, instructor/coach observations, etc, and some empirical factors, such as: time measurements, post run video analysis, while the safety and comfort depends on decades old ski binding technology, incremental progress in materials and manufacturing technology.
Some analytical methods for data collection during the development phase of the ski equipment are in use today, however, most of those techniques are not practical for the every day training of professional or recreational skier, as they require bulky equipment and require large team of highly skilled technicians to operate.
It is well known that the safety of skiing depends predominantly on ski bindings. Currently, binding safety is defined by the stiffness of it's spring(s) used to hold/release ski boot, which is adjusted according to the presumed capability of the user and the user weight. This basic principle of ski binding didn't changed in past 40 years (also many incremental improvements, such as: multi-pivots/springs were added), and perform satisfactory most of the time—when the speeds are modest, the spring pre-set torque was below the critical level and the user is physically fit, the fundamental problem—relying on intuition for setting the spring strength and fact that in almost all cases, only one of the binding, the one experiencing excessive force, will release. This is mainly to the fact that the forces applied to both skis and/or skis trajectory are not the same. In effect, while one ski is released the other, the other is still attached to the user causing serious injuries during a fall, a major source of trauma to the knee's Anterior Cruciate Ligament (ACL).
This type of injury is induced via a torque mechanism (so called “Phantom Foot”), when the skier looses balance backward while the skis are still turning. While this occurs, a majority of the skier's weight is on the tail of the downhill ski (that is, the ski closest to the base of the ski run). Due to the loss in balance, the skier is unable to turn properly, and momentum keeps his or her body headed down the hill. Unfortunately, the downhill ski is still turning, and continues turning. The turning ski rotates the boot internally, which causes internal rotation of the foot. This in turn rotates the lower leg inward relative to the thigh. This leads to the ACL becoming stretched, then sprained, and if the breaking point is reached, it tears.
Another type of common knee injury referred as “forward falling” occurs when front of the inside edge of one ski starts “dragging” on the snow—this is common when the ski trajectory diverge outwards, causing external tibial rotation, which in combination with forward velocity extends the knee.
Current monitoring systems are not practical for every day use and analysis of the run is lest to subjective interpretation, while the safety of the skiing, provided mainly by the ski bindings, is left virtually unchanged for the past thirty years.
In recent years, the use of mobile devices and, in particular, cellular telephones has proliferated. Today, cellular phone besides providing basic communication over cellular network is equipped with various input/output capabilities, such as wireless PAN (Personal Area Network), and provides significant computing resources. When such computing resources communicate with the remote sensors, such as MEMS accelerometers, magnetometers, gyroscopes, pressure sensors, actuators the resulting system can provide various sport analytical tools for monitoring of skiing.
By coupling MEMS accelerometers and actuators embedded in the ski equipment with an analysis application residing in the user smart-phone, one can provide tool analyzing forces experienced by the user and increase in safety and comfort of skiing. Furthermore, using the smart-phone connectivity to the wireless cellular network, a real-time feedback to the remote location may be provided to add in ski testing or training. System described in this invention can operate using any of wireless technology such as: cdma2000, UMTS, WiMax, LTE. LTE-A, etc.